Why do you feel out of breath when you exercise?
Active metabolism is producing more carbon digide, which decreases the pH of your blood, trigering homeostatic pathways which stimulate deeper, faster breathing.
Active metabolism is corruming ongen more quikly, activating homeostatic mechaniums which triezer these feelings and stimulate deeper, faster breathing.
As your musdes run out of O_(2), they begin peoducing lactic acid, decreasing blood pH. Our bodies can't tell the difference between phi decrease from lactic acid buld up and pH decrease from CO_(2) levels, so it trigeers deeper, faster breathing.
None of the above